dwarf2out.c (output_line_info): Don't emit redundant info.

	* dwarf2out.c (output_line_info): Don't emit redundant info.
	Do start a new row if the file changes and the line # doesn't.

From-SVN: r26061

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1045c8bb7321a45711ef29b8c43c407709d207c7..715422e5128d5d321e5401234250e07448bfa899 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+Tue Mar 30 00:26:34 1999  Jason Merrill  <jason@yorick.cygnus.com>
+
+       * dwarf2out.c (output_line_info): Don't emit redundant info.
+       Do start a new row if the file changes and the line # doesn't.
+
 Mon Mar 29 15:48:39 1999  Jason Merrill  <jason@yorick.cygnus.com>
 
        * invoke.texi (Invoking G++, C++ Dialect Options): Update.

diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 50d6937eb855aecebc3f360263cada58fe348aa0..393dbc54323ba010dc223953717889ea85e419d0 100644 (file)
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -4826,14 +4826,15 @@ size_of_line_info ()
   /* Prolog.  */
   size += size_of_line_prolog ();
 
-  /* Set address register instruction.  */
-  size += size_of_set_address;
-
   current_file = 1;
   current_line = 1;
   for (lt_index = 1; lt_index < line_info_table_in_use; ++lt_index)
     {
-      register dw_line_info_ref line_info;
+      register dw_line_info_ref line_info = &line_info_table[lt_index];
+
+      if (line_info->dw_line_num == current_line
+         && line_info->dw_file_num == current_file)
+       continue;
 
       /* Advance pc instruction.  */
       /* ??? See the DW_LNS_advance_pc comment in output_line_info.  */
@@ -4842,7 +4843,6 @@ size_of_line_info ()
       else
        size += size_of_set_address;
 
-      line_info = &line_info_table[lt_index];
       if (line_info->dw_file_num != current_file)
        {
          /* Set file number instruction.  */
@@ -4886,6 +4886,12 @@ size_of_line_info ()
     {
       register dw_separate_line_info_ref line_info
        = &separate_line_info_table[lt_index];
+
+      if (line_info->dw_line_num == current_line
+         && line_info->dw_file_num == current_file
+         && line_info->function == function)
+       goto cont;
+
       if (function != line_info->function)
        {
          function = line_info->function;
@@ -4928,6 +4934,7 @@ size_of_line_info ()
            }
        }
 
+    cont:
       ++lt_index;
 
       /* If we're done with a function, end its sequence.  */
@@ -5834,18 +5841,9 @@ output_line_info ()
   ASM_OUTPUT_DWARF_DATA1 (asm_out_file, 0);
   fputc ('\n', asm_out_file);
 
-  /* Set the address register to the first location in the text section */
-  ASM_OUTPUT_DWARF_DATA1 (asm_out_file, 0);
-  if (flag_debug_asm)
-    fprintf (asm_out_file, "\t%s DW_LNE_set_address", ASM_COMMENT_START);
-
-  fputc ('\n', asm_out_file);
-  output_uleb128 (1 + PTR_SIZE);
-  fputc ('\n', asm_out_file);
-  ASM_OUTPUT_DWARF_DATA1 (asm_out_file, DW_LNE_set_address);
-  fputc ('\n', asm_out_file);
-  ASM_OUTPUT_DWARF_ADDR (asm_out_file, text_section_label);
-  fputc ('\n', asm_out_file);
+  /* We used to set the address register to the first location in the text
+     section here, but that didn't accomplish anything since we already
+     have a line note for the opening brace of the first function.  */
 
   /* Generate the line number to PC correspondence table, encoded as
      a series of state machine operations.  */
@@ -5854,7 +5852,14 @@ output_line_info ()
   strcpy (prev_line_label, text_section_label);
   for (lt_index = 1; lt_index < line_info_table_in_use; ++lt_index)
     {
-      register dw_line_info_ref line_info;
+      register dw_line_info_ref line_info = &line_info_table[lt_index];
+
+      /* Don't emit anything for redundant notes.  Just updating the
+         address doesn't accomplish anything, because we already assume
+         that anything after the last address is this line.  */
+      if (line_info->dw_line_num == current_line
+         && line_info->dw_file_num == current_file)
+       continue;
 
       /* Emit debug info for the address of the current line, choosing
         the encoding that uses the least amount of space.  */
@@ -5898,7 +5903,6 @@ output_line_info ()
 
       /* Emit debug info for the source file of the current line, if
         different from the previous line.  */
-      line_info = &line_info_table[lt_index];
       if (line_info->dw_file_num != current_file)
        {
          current_file = line_info->dw_file_num;
@@ -5916,35 +5920,48 @@ output_line_info ()
 
       /* Emit debug info for the current line number, choosing the encoding
         that uses the least amount of space.  */
-      line_offset = line_info->dw_line_num - current_line;
-      line_delta = line_offset - DWARF_LINE_BASE;
-      current_line = line_info->dw_line_num;
-      if (line_delta >= 0 && line_delta < (DWARF_LINE_RANGE - 1))
+      if (line_info->dw_line_num != current_line)
        {
-         /* This can handle deltas from -10 to 234, using the current
-            definitions of DWARF_LINE_BASE and DWARF_LINE_RANGE.  This
-            takes 1 byte.  */
-         ASM_OUTPUT_DWARF_DATA1 (asm_out_file,
-                                 DWARF_LINE_OPCODE_BASE + line_delta);
-         if (flag_debug_asm)
-             fprintf (asm_out_file,
-                      "\t%s line %ld", ASM_COMMENT_START, current_line);
+         line_offset = line_info->dw_line_num - current_line;
+         line_delta = line_offset - DWARF_LINE_BASE;
+         current_line = line_info->dw_line_num;
+         if (line_delta >= 0 && line_delta < (DWARF_LINE_RANGE - 1))
+           {
+             /* This can handle deltas from -10 to 234, using the current
+                definitions of DWARF_LINE_BASE and DWARF_LINE_RANGE.  This
+                takes 1 byte.  */
+             ASM_OUTPUT_DWARF_DATA1 (asm_out_file,
+                                     DWARF_LINE_OPCODE_BASE + line_delta);
+             if (flag_debug_asm)
+               fprintf (asm_out_file,
+                        "\t%s line %ld", ASM_COMMENT_START, current_line);
 
-         fputc ('\n', asm_out_file);
+             fputc ('\n', asm_out_file);
+           }
+         else
+           {
+             /* This can handle any delta.  This takes at least 4 bytes,
+                depending on the value being encoded.  */
+             ASM_OUTPUT_DWARF_DATA1 (asm_out_file, DW_LNS_advance_line);
+             if (flag_debug_asm)
+               fprintf (asm_out_file, "\t%s advance to line %ld",
+                        ASM_COMMENT_START, current_line);
+
+             fputc ('\n', asm_out_file);
+             output_sleb128 (line_offset);
+             fputc ('\n', asm_out_file);
+             ASM_OUTPUT_DWARF_DATA1 (asm_out_file, DW_LNS_copy);
+             if (flag_debug_asm)
+               fprintf (asm_out_file, "\t%s DW_LNS_copy", ASM_COMMENT_START);
+             fputc ('\n', asm_out_file);
+           }
        }
       else
        {
-         /* This can handle any delta.  This takes at least 4 bytes, depending
-            on the value being encoded.  */
-         ASM_OUTPUT_DWARF_DATA1 (asm_out_file, DW_LNS_advance_line);
-         if (flag_debug_asm)
-           fprintf (asm_out_file, "\t%s advance to line %ld",
-                    ASM_COMMENT_START, current_line);
-
-         fputc ('\n', asm_out_file);
-         output_sleb128 (line_offset);
-         fputc ('\n', asm_out_file);
+         /* We still need to start a new row, so output a copy insn.  */
          ASM_OUTPUT_DWARF_DATA1 (asm_out_file, DW_LNS_copy);
+         if (flag_debug_asm)
+           fprintf (asm_out_file, "\t%s DW_LNS_copy", ASM_COMMENT_START);
          fputc ('\n', asm_out_file);
        }
     }
@@ -5994,6 +6011,12 @@ output_line_info ()
       register dw_separate_line_info_ref line_info
        = &separate_line_info_table[lt_index];
 
+      /* Don't emit anything for redundant notes.  */
+      if (line_info->dw_line_num == current_line
+         && line_info->dw_file_num == current_file
+         && line_info->function == function)
+       goto cont;
+
       /* Emit debug info for the address of the current line.  If this is
         a new function, or the first line of a function, then we need
         to handle it differently.  */
@@ -6094,10 +6117,21 @@ output_line_info ()
              output_sleb128 (line_offset);
              fputc ('\n', asm_out_file);
              ASM_OUTPUT_DWARF_DATA1 (asm_out_file, DW_LNS_copy);
+             if (flag_debug_asm)
+               fprintf (asm_out_file, "\t%s DW_LNS_copy", ASM_COMMENT_START);
              fputc ('\n', asm_out_file);
            }
        }
+      else
+       {
+         /* We still need to start a new row, so output a copy insn.  */
+         ASM_OUTPUT_DWARF_DATA1 (asm_out_file, DW_LNS_copy);
+         if (flag_debug_asm)
+           fprintf (asm_out_file, "\t%s DW_LNS_copy", ASM_COMMENT_START);
+         fputc ('\n', asm_out_file);
+       }
 
+    cont:
       ++lt_index;
 
       /* If we're done with a function, end its sequence.  */